Directional mounting for a gun



Oct. 1, 1957 R. G. VICKERS 2,307,987

DIRECTIONAL MOUNTING FOR A GUN Filed July 16, 1954 3 Sheets-Sheet 1INVENTDR my GILBEW' Iva 5P5,

ATTDHNEY Oct. 1, N57 R. e. VICKERS DIRECTIONAL MOUNTING FOR A GUN 3Sheets-Sheet 2 Filed July 16, 1954 IN VE N TOR Kay east-le wave/as,

ATTORNEY R. cs. VICKERS 2,807,987

DIRECTIONAL. MOUNTING FOR A GUN 5 Sheets-Sheet 3 Filed July 16, 1954' MMATTDHNEY United. States atent Patented Oct. 1, 1957 DIRECTIONAL MOUNTINGroa A GUN Roy Gilbert Vickers, Grantham, England, assignor to Brevets'Aero-Mecaniques S. A., Geneva, Switzerland, a society of SwitzerlandApplication July 16, 1954, Serial No. 443,861

Claims priority, application Great Britain July 22, 1953 6 Claims. (Cl.89-41) This invention relates to mountings for apparatus to be directedor aimed by an operator on the mounting and it will be described asapplied to a gun mounting. The invention can however be applied to otherdirectional mountings such as for searchlights, radarapparatus ortelevision or other cameras.

The object of the invention is to provide improved means to enable anoperator seated on a mounting to train the mounting, that is to turn themounting about a normally vertical central axis, by the power andcontrol of his feet on a pair of pedal levers.

Pedal lever training mechanism for gun mountings already knowncomprises, fixed on the base of the mounting, a horizontal circular rackcoaxial with a turntable or equivalent part of a training structurewhich carries a pinion meshing with the rack and driven, throughtransmission gearing, by a pair of pedal levers to turn the trainingstructure about the rack.

Rack and pinion training mechanisms with other drives, such ashand-wheel drives, also are known and in fact some form of rack andpinion, or worm and worm-wheel, has been the standard means of trainingmountings.

The present invention has a different principle, requiring no toothedgearing, and provides means enabling an operator to thrust with his feeton pedal levers and obtain a purchase against the base of the mountingfrom which to turn, just as though he were able to apply his feetdirectly to the base but with the advantages of additional leverage anda simple leg action as compared with the rather complex action of athrust exerted through the operators seat from the ground or a fixedpedal.

The invention is applied to a directional mounting comprising a baserotatably supporting a turntable or equivalent part of a trainingstructure provided with a pair of pedal training levers for actuation byan operator on the training structure and, according to the invention,the base has a fixed circular track coaxial with the training axis, theturntable has, journalled relatively thereto and coaxially therewith, apair of arms extending radially in opposite directions from the trainingaxis to the circular track, each arm is spring-loaded, to a givenangular position relatively to the turntable, and each arm has a shoe toengage against the track, to provide a fixed point from which theturntable can be turned, under thrust transmitted through connectingmeans from one of the pedal levers respectively. 1

Conveniently the track is provided by the smooth inside cylindricalsurface of an upstanding base ring, the shoes are simple friction shoespivoted in the arms and the connection between each shoe and itsrespective pedal lever consists of a cam lever pivoted in the arm tobear on the shoe and a connecting rod universally jointed to the camlever and pedal lever respectively.

The spring-loading of each arm, conveniently provided at the axis by ahelical torsion spring with crossed ends,

is eifective also on the pedal lever to which its shoe is connected andpreferably it is arranged so thatin the normal position the pedal leveris vertical and the arm and the pedal lever have movement, relatively tothe training structure, equally in both directions from, the normalposition, against the spring-loading, up to the limit of stops on thetraining structure.

The invention as applied to a gun mounting is illustrated on thedrawings accompanying the provisional specification, in which: i

Fig. 1 is a side elevation of a light anti-aircraft gun mounting.

Fig. 2 is a side elevation on a larger scale, partly broken away, of thebase and of the turntable which carries the remainder of the trainingstructure of the mounting shown by Fig. 1.

Fig. 3 is an axial half-section through the base and turntable of Fig.2, taken on the line lII-III of Fig. 4 and Fig. 4 is a fragmentary plan,partly broken away and partly in section, of the base and turntable ofFig. 2 with some parts omitted for clarity of illustration.

The mounting shown by the drawings has a circular base 1 held down on ahorizontal support, such as the deck of a ship, by bolts passed throughholes 2. (See Fig. 3.) The base has a stout central pivot 3 and, towardsits periphery, an upstanding flange ring 4 which respectively supportroller bearings 5 and 6 at the inner and outer peripheries of an annularturntable 7 which is thus mounted to turn easily but truly on the baseand to carry the load of the remainder of the training structure. Theturntable 7 is of inverted dish shape.

As shown by Fig. l, on the turntable 7 is built a turret cabin 8 inwhich is cradled a pair of guns 9, only one of which appears in Fig. 1,provided with hand-lever elevating or laying controls 10, and a sight 11for a gunner on a seat 12'. The detailed construction and operation ofthe cabin and guns are not relevant to the present invention which isconcerned only with training the mounting by turning of the turntable 7on the base 1.

The training mechanism will now be described with particular referenceto that part operated by thrust of the gunners left foot for trainingthe mounting tothe right. This left-foot mechanism is shown'in detail bythe drawings and it will be remembered that it is duplicated, with thenecessary lateral inversion, on the other side of the mounting for theright-foot drive.

Convenient to each of the gunners feet is a pedal lever which will bereferred to generally by the reference number 13 but, as shown in Figs.2 and 3, in fact comprises a pedal or foot-bar 13, a pedal arm 13 across-shaft 13. in a pillow-block bearing 14 on the turntable 7, and adrop-arm 1?) extending down into the interior of the turntable 7 througha slot therein (not shown). The pedal lever has a normal verticalposition and a movement of about 30 on each side of the vertical. on theturntable 7 to be encountered by the drop-arm 13 provides a stoplimiting forward movement of the pedal lever. (See Fig. 2.)

The lower end of the drop-arm 13 is formed as-a socket seat to make ajoint with one ball-end of a dumbbell shaped connecting rod 16 the otherend of which (see Fig. 4) is similarly jointed to the radially inner endof a cam lever 17 pivoted by a vertical pin 18 in the outer end of aradial arm 19 journalled by plain bearing bushes 20 on the central pivot3. Fig. 3 shows how the two arms 19 are knuckle-jointed around the pivot3 so as to lie in the same horizontal plane and have bearin g surfacesof adequate overall length.

Around a spacer ring 21 on the central pivot 3 is coiled a helicaltorsion spring 22, one for each arm 19. The ends of the spring 22 areset to project substantially radially and the spring is pro-loaded sothat its ends cios's An abutment 15 one another and anchorcircumferentially in opposite directions against axial pins 23 and 24fixed in the turntable 7 and arm 19 respectively. (See Figs. 3 and 4.)Thus the spring 22 tends to maintain the arm 19 in a givenpositionrelatively'to the turntable 7. This position is shown in the drawingsand is that in which the pins 23 and 24 are radially aligned, under theload applied equally and oppositely by the .ends of the spring 22against the pin 24. The spring 22. acting on the arm 19 also thrusts orpulls on the pedal lever 13 through the connecting rod 16 and thus alsoacts as a return spring for the pedal lever tending always to return thepedal lever to its vertical position as shown.

Angular movement of the turntable 7 relatively to the arm 19, in thedirection to move the pedal 13 rearwardly, islimited by an abutment 25on the inside of the turntable arranged to encounter a boss 26 on thearm 19. (See Fig. 4.) This also limits rearward movement of the pedal13. The abutment 15 for the drop-arm 13 (see Fig. '2)", by limitingforward movement of the'pedal, limits angular movement of the arm 19relatively to the turntable 7 in the rearward direction away from thepedal lever.

In the extreme outer end of the arm 19 is pivoted by a vertical pin 27(see Fig. 4) a shoe 28 having a plain friction surface presented againsta track 29 provided by. the smooth inside cylindrical surface of the rimof the flange ring 4. It will be noted that the base 1 has radial ribs 1and integral gusset stays 1 bracing and supporting the flange ring 4. V

The cam lever 17 has a half-round self-aligning pressure pad 30 (seeFig. 4) through which to apply the shoe 28 against the track 29 underthe thrust of the pedal lever 13 acting through the connecting rod 16. Apullofi spring 31 is stretched between the toe of the shoe 28 and ananchorage on the arm 19 and a nut 32 on a stud 33 adjustably limitsturning of the cam lever 17 away from the shoe 28.

The action of the mechanism is as follows:

In the normal position, the pedal lever 13 is vertical under theinfluence of the respective spring 22 on the arm 19, the shoe 28 isclear of the track 29 and the turntable 7 carrying the trainingstructure is free to move on its bearings about the central pivot 3 ofthe base 1.

Initial thrust of the gunners foot on a pedal lever 13, acting throughthe connecting rod 16 and cam lever 17, applies the shoe 28 firmlyagainst the track 29. This provides a purchase. fixing the arm 19relatively to the base 1 and continued thrust on the pedal lever, actingabout the forward end of the connecting rod as a basefixed fulcrum,turns the whole training structure until the drop-arm 13 encounters thestop 15.

'Itshould be noted that the initial thrust on the pedal lever 13 mustovercome the tension of the pull-off spring 31 in order to turn the shoe28 towards the track and that the spring 22 must be strong enough tohold the arm 19 against such initial thrust until the shoe 28 holdsagainst the track and thus fixes the arm 19.

During the training movement under the thrust on the pedal lever 13,the-pin 23 fast with the turntable 7 entrains in its movement the end 22of the spring 22 whilst the other end 22 remains held by the pin 24 inthe arm 19.

On release of the pedal lever, the pressure on the shoe '28 is relievedand the shoe is pulled by its spring 31 clear of the track 29 allowingthe arm 19 to follow up the training structure under the torsion of thespring 22 applied through the end 22 against the pin 24. This alsoreturns the pedal lever to the vertical position.

The arm 19 is now ready for the shoe 28 to take a 'fresh purchaseagainst the track 29 and thus provide a new fixed point for furthertraining under the next thrust on the pedal lever. Each stroke of thepedal lever can be as short or as long, within its limits, as the gunnerdesires.

If the thrust on the pedal lever is light, as in tracking a target, thetraining structure will have a dead-beat motion with and proportional toforward pedal movement.

If however a heavier thrust is made on the pedal lever, as in slowing,the training structure will gain momentum and at the end of the forwardstroke of the pedal lever, when the load on the pedal has been taken bythe stop 15, the pressure of the shoe against the track will relaxsufliciently to allow the arm 19 to move with the training structure solong as the latter coasts-or free-wheelsunder the impetus of the thruston the pedal lever.

The initial relaxation of the pressure of the shoe against the track isdue to transfer of pedal load to the stop 15 and the eventual degree ofrelaxation is determined by the balance of the pull-off spring 31against the follow-up effort of the spring 22, the latter acting,through the arm 19 and the pin 18, on the cam lever 17 about the rearend of the connecting rod 16 as a fulcrum fixed by the pedal level beingheld forward. It can be arranged'that any resultant pressure of the shoeagainst the track, while the pedal lever isheld forward, is so slight asnot to affect rotation of the mounting.

The arm 19 will not recover its original angular position relatively tothe turntable until the pedal lever is released to allow the spring 22to bring the pin 24 into alignment with the pin 23, but this can ofcourse be done during the coasting period to be ready for another thruston the pedal lever.

It will be remembered that the mechanism is duplicated, for the twodirections of training. Both pedal levers may be thrust simultaneouslyto engage their shoes and fix the two arms against the track. From thisposition, differential 'movement of the gunners feet, equal and oppositewith the two pedal levers within the limits of the stops, producesdirectly a corresponding movement of the training structure as thoughthe pedals were on the ends of a rudder bar.

Either pedal lever can be applied as a brake, to check slewing of themounting resulting from thrust on the other pedal lever, the brakinglever holding its shoe fast against the track and being forced backagainst. the thrust of the gunners foot until the training structure hasturned sufiiciently for the abutment 25 on the turntable 7 to encounterthe boss 26 on the arm 19 whereupon the shoe is dragged round the trackas a friction brake. This friction braking would only be required toarrest a fast traverse of the mounting. Moderate-speed slewing can beopposed and stopped by thrust of the gunners foot.

The training mechanism of the present invention provides the gunner, orthe operator of any similar direc tional mounting, with the facility totrain his mounting instinctively and with the same fineness of controlas,

and even greater strength'than, he would have with his feet directly onthe base or ground.

The above description and the drawing referred to, illustrate onepractical embodiment of the invention but modifications could of coursebe made.

For example, the opposed faces of the shoe 28 and track 29 being simplefriction surfaces, they have, in the absence of slip, an infinitecapacity for interengagement throughout the training circle. With someloss in infinite finenessof angular position, the interengagement ofthese faces could be made positive, such as by the provision of veryfine axial serrations to avoid the possibility of slip although thiswould'complicate the braking action. However, by so proportioning theleverages of the pedal lever and cam lever it can be ensured that thefriction torque of the'shoe on the track is always greater than thetorque available to turn the mounting so that .slip is avoided, evenwith the relatively low coefiici'entof friction for opposed plain metalsurfaces subject to intermittent lubrication. Consequently plain ormetal or metal-faced shoes are preferred.

Another possible modification is that the transmission of pedal pressureto the shoe could be hydraulic instead of mechanical, means beingprovided relieving the hydraulic pressure to release the shoe forcoasting of the mounting when the pedal has been thrust against itsstop.

What I claim is:

l. A directional mounting which comprises, in combination, a base, atraining structure support rotatable on said base about a training axisperpendicular to said base, a circular track fast on said base andcoaxial with said training axis, a pair of pedal levers pivoted on saidsupport and adapted to be thrust respectively by the feet of an operatorseated on said support, a pair of arms angularly movable about saidtraining axis relatively to both said base and said support, said armsextending separately from said training axis radially towards saidtrack, springloading means urging each of said arms respectively to agiven angular position relatively to said support, a shoe on each saidarm and movable relatively to said arm so as to engage against anddisengage from said track, and means connecting one of said pedal leversto one of said shoes and the other of said pedal levers to the other ofsaid shoes, said connecting means being arranged to transmit thrust fromthe respective pedal lever to the respective shoe to engage said shoeagainst said track and thereby provide a fixed point purchase formovement of said pedal lever to rotate said support on said base.

2. A directional mounting according to claim 1, in which each said shoeis pivoted on the respective arm and the means connecting the respectivepedal lever to said shoe comprises, a cam lever pivoted on the same armas said shoe and bearing on said shoe to move said shoe against saidtrack and a connecting rod universally jointed at one end thereof tosaid cam lever and at the other end thereof to the respective pedallever.

3. A directional mounting according to claim 2, in which a pull-offspring is provided between each said shoe and the respective arm to urgesaid shoe away from said track and against said cam lever.

4. A directional mounting according to claim 1, in which each said pedallever is pivoted on said support 6 about an axis parallel to the planeof said base and abutments are provided on said support, said abutmentslimiting angular movement of each said pedal lever to an arc of movementsubstantially equal on either side of a position in which saidrespective pedal lever is substantially perpendicular to said base.

5. A directional mounting according to claim 1, in which saidspring-loading means comprises a pair of helical torsion springs locatedcoaxially about said training axis, each said spring having its endscrossed one over the other and projecting substantially radially fromsaid training axis, and, for each of said springs, a pair of anchor pinsengaged by the crossed ends of the respective spring, one pin of eachpair being fast on said support and the other pin of said pair beingfast with the respective arm.

6. In a directional mounting comprising a base, a training structuresupport rotatable on said base and pedal means for an operator on saidsupport to rotate said support on said base; a circular track fast onsaid base and axially perpendicular to said base, purchase meansoperative between said pedal means and said circular track to provide apurchase for said pedal means against said track, and comprising a pairof arms angularly movable about the axis of said track relatively toboth said base and said support, said arms extending separately andradially towards said track, spring-loading means urging each of saidarms to a given angular position relatively to said support, and a shoeon each of said arms, said shoe being directed towards said track andpivoted on the respective arm to engage against said track under thrustfrom said pedal means and means interconnecting said pedal means andsaid shoes.

References Cited in the file of this patent FOREIGN PATENTS

